The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 26, 2010
Filed:
Aug. 09, 2004
Applicants:
Nobuhiko Kikuchi, Tokyo, JP;
Kenro Sekine, Fuchu, JP;
Shinya Sasaki, Koganei, JP;
Inventors:
Assignee:
Hitachi Communication Technologies, Ltd., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
H04J 14/02 (2006.01);
U.S. Cl.
CPC ...
Abstract
Part of an inputted optical add signalis reflected by a mirror, and is thereby inputted into an optical wavelength multiplexerin the reverse direction so that the optical add signal is returned to paths-through-corresponding to wavelengths λthrough λ. If the returned optical add signal is an optical add signal having a correct wavelength, the optical signal enters its corresponding backward direction optical detector-. Accordingly, it is possible to check whether or not a wavelength of the optical add signal is correct.